Bow thruster



Feb. 27, 1968 F. E. PARSONS BOW THRUSTER Filed Jan. 21, 1966 //v VENTOR.f l zi 5 74730775 3,370,541 BOW THRUSTER Fred E. Parsons, 1656 KellerLane, Bloomfield Hilts, Mich. 48013 Filed Jan. 21, 1966, Ser. No.522,248 6 Claims. (Cl. 103-88) ABSTRACT OF THE DISCLOSURE The inventionpertains to a device which provides a flow of water from either side ofthe bow of a ship for propelling the bow to the right or to the left toassist in maneuvering the ship in a small area.

This invention relates to fluid propulsion devices and particularly to apropulsion device which produces right and left thrust to the bow of aboat.

Because of the length of boats, ships and liners relative to theirWidth, it is ditiicult to handle the boat in limited areas. Tugs areusually depended upon for moving the large steamers and liners into andout of dock facilities and otherwise maneuvering them in cramped areas.The bow thruster of the present invention moves the bow of the boattransversely of its length and permits the large crafts to be controlledand maneuvered in restricted areas.

The bow thruster of the present invention has like right and left handhousings in which rotors are mounted along with drive and brakemechanisms for locking one of the rotors while driving the other so thatthe flow of water through the device may either be to the right or tothe left. The direction of How of the water may be quickly changed byreleasing one brake'and applying the other. In the example illustrated adifferential drive is employed which drives one rotor when the other ismaintained stationary. Magnetic brakes are illustrated as being theholding means for the rotors.

Accordingly, the main objects of the invention are: to provide a bowthruster having like fluid propelling means at each end thereof; toemploy drive means for the propelling means at each end of thepropelling device with brake means for retaining one of the propellingmeans stationary while the other is being driven; to provide a devicefor propelling a like flow of water from either end thereof controlledby the application of brake means to one of two like propelling means,and in general, to provide a bow thruster which is simple inconstruction, positive in operation and economical of manufacture.

Other objects and features and novelties of the invention will bespecifically pointed out or will become apparent when referring, for abetter understanding of the invention, to the following descriptiontaken in conjunction with the accompanying drawing. wherein:

The figure is a sectional view of a bow thruster embodying features ofthe present invention.

The bow thruster of the present invention has an outer shell 10 made upof a left-hand truncated conical housing 11 and a right-hand truncatedconical housing 12 of the same shape and dimensions. A central section13 is made up in two parts 14 and 15 which are secured together by aseries of bolts 16. The housing sections 11 and 12 have flanges 17thereon which are secured to the central section 13 by a series of bolts18. A similar flange 19 is provided in the forward end of the housingsections 11 and 12 having apertures 21 therethrough by which the flangeis secured to an intake and outlet conduit.

The central section 13 supports a drive differential 22 on bearings 23.The difierential 22 is driven by a ring gear 24 having sloping teeth 25Which mate with sloping teeth 26 of a bevel, hypoicl or like gear 27.The gear 27 is supported on a shaft 28 which is mounted in bearingsUnited States Patent 0 3,379,541 Patented Feb. 27, 1968 ice 29 on thecentral section 13. The shaft extends through one of a plurality of webs30 which provide passageways 36 for the water through the centralsection 13 in continuation of the axial passageways through the housingsections 11 and 12. The web 30 herein illustrated is of greater widthnear the center portion to enclose the shaft 28 and is streamlined toreduce resistance of the passage of water thereover. The other webs arethinner and preferably of uniform thickness.

The differential 22 carries a stub shaft 31 which is secured againstrotation by a pin 32. Bevel gears 33 and 34 are mounted for rotation onthe shaft 31 with their teeth in engagement with side bevel gears 35.The latter gears are splined to splines 37 of shafts 38 which aresupported in sleeve bearings 39 and by outboard truncated rollerbearings 41. The bearings 41 engage the inner surface of cup-likesleeves 42 which are secured by screws 43 within the aperture inextending arms 44 provided on the central section 13.

Electrically energizable coils 45 are carried on the inner or closed endof the sleeve 42 to provide a magnetic flux when energized by a circuitincluding a pair of leads within conduits 46. The flux path is completedby a Z- shaped annular member 47 which is splined to a splined section48 of the shaft 38. Upon the energization of the coil 45, the magneticflux produced thereby forms a path about the coil through the sleeve 42and member 47 to lock the sleeve and member together and secure theshaft to the arm 44 against rotation. An ogive shaped hub 49 is securedto splines 51 on each shaft 38 locked in position by a nut 52 and endcap 53. The hubs 49 carry a plurality of vanes 54 extending outwardlythereof and preferably enclosed within a shroud 55. The vanes may bestraight, located parallel to the axis of the shaft, or may be curved alimited amount since the flow of liquid from one of the sections to theother will pass between the vanes and function somewhat as straighteningvanes in the section having the rotor which is retained stationary tofunction as'a stator.

In operation the shaft 28 is driven from a suitable source of power andone of the magnetically operated brakes will be energized so that theother will be driven. If the magnetic brake in the left-hand section 11is energized, its hub 49 and vanes 54 will be retained stationary whilethe hub and vanes of the right-hand section 12 will be rotated forcingthe water from the right through the central section and out through theleft-hand section to force the bow of the boat to the right. When theelectromagnetic brake on the left-hand side is deenergized and that onthe right-hand side is energized, the hub and vanes on the left-handsection will be driven thus causing the flow of water from the left tothe right and forcing the bow of the boat to the left. The circuitsthrough the leads of the conduits 46 are preferably interlocked, as by aswitch 56, so that both of the circuits cannot be energized at the sametime, otherwise damage could occur to the driving mechanism and thedriven parts of the device. With the left and right-hand sections of thedevice constructed exactly alike, the same flow of water will occurwhether the hub of the left or right-hand section is rotated and thesame thrust will be produced either to move the bow of the boat to theright or to the left. It is to be understood that the drivingdifferential and the magnetic brakes have been shown more by way ofexample and that turbines and other types of drives as Well as differentbrake mechanisms known in the art to be suitable may be substituted forthose herein illustrated.

What is claimed is:

1. A bow thrusting device having substantially identical housings ateach end joined to a central section, drive means housed within thecentral section, a pair of axially disposed shafts rotatable within thehousings selectively driven by said drive'means, rotors on said shaft ofsubstantially identical construction, and brake means for locking one orthe other rotor so that the drive means will drive the unlocked rotor toproduce a flow of water over the locked rotor which functions as astator.

2. A device as recited in claim 1 wherein the'drive means embodies adifferential housing for driving side gears from a pair of driven piniongears.

3. A device as recited in claim 1 wherein brake means is carried betweenthe central section and each of the shafts.

4. A device as recited in claim 3 wherein the brake means aremagnetically operated brake devices.

5. A device as recited in claim 1 wherein the brake means for lockingone shaft is interlockedwith that for locking the other shaft so thatonly one brake means can be operated at one time to lock a rotor.

6. A device as recited in claim 2, wherein brake means is carriedbetween the central section and each of the shafts.

References Cited UNITED STATES PATENTS 1,402,059 1/1922 Eich 103-941,972,780 9/1934 Laskowitz 230--123 3,044,260 7/1962 Hamilton 2301233,112,610 12/1963 Jerger l0394 3,127,865 4/1964 Pleug'er 2301233,225,537 12/1965 Parsons 103-88 3,269,111 8/1966 Brill 10394 FOREIGNPATENTS 586,567 3/1947 Great Britain.

586,568 3/ 1947 Great Britain.

587,529 4/1947 Great Britain.

HENRY F. RADUAZO, Primary Examiner.

